This invention relates to the manufacture of rolls of fibrous web material, and especially to improvements in releasably securing the tail or terminal portion of the outer layer of the web material to successive underlying layers.
Improvement resides in provision of securement means that requires no adhesive, and is readily releasable without tearing the layers upon unwinding the roll.
The following U.S. Pats. are representative of the prior art, and are believed material to the examination of this application.
U.S. Pat. No. 3,393,105 discloses a method and apparatus for adhesively securing the tail of a product to the underlying convolution thereof.
U.S. Pat. No. 3,448,502 discloses a method for producing textile goods containing an upper layer and a base layer by means of needling.
U.S. Pat. No. 3,451,885 discloses a composite web formed by needling a plurality of webs.
U.S. Pat. No. 3,366,529 discloses a fibrous fleece needled to a base film of thermoplastic material.
Further to the prior art of which applicant is aware, it is known to secure the tail of a roll of fibrous web material by tangentially penetrating wound layers of a roll with laterally spaced parallel needles to a depth of about 3 to about 5 layers, in a direction opposite to the direction of presentation of the tail. Securement of this type has proven satisfactory for rolls of web material that are relatively loosely wound and characterized by high bulk. For rolls of this type, needle securement is readily released upon initially unwinding the roll, without tearing of the secured layers. When the same mode of securement was resorted to for lower bulk rolls of more tightly wound web material, the needled securements were found not readily releasable upon unwinding of the tail, often resulting in stringing or tearing of the layers.
We have made the important discovery that by repositioning the needles tangentially to penetrate the layers in the same direction of presentation of the tail achieves a needled securement that overcomes the problem of stringing.
It is accordingly an objective of our invention to provide improved tail securement of a roll of fibrous web material.
It is a further objective to provide an improved tail securement for a roll of web material that is readily releasable without damage to the material.
It is another objective to provide improved tail securement for a roll of relatively tightly wound fibrous web material.